Measles virus (MeV) recognizes and fuses with target cells via hemagglutinin (H) and fusion (F) proteins, respectively. To achieve T cell-specific transduction, Ibrahim et al. produced a lentivirus (LV) expressing MEV-F and a re-targeted MEV-H linked to a targeting molecule (VHHs resulted in higher functional titers than scFvs). To avoid serum neutralization by anti-MeV antibodies, MeV-H/F proteins were redesigned as chimeras with dolphin morbillivirus-H/F. LVs expressing the chimeric proteins, CD7-targeting VHH, and anti-CD3 and CD80 (activation cues) generated CD19 CAR T cells in vivo and slowed Nalm6 tumor growth. CAR expression was largely restricted to T cells.
Contributed by Alex Najibi
ABSTRACT: Despite striking efficacy against hematologic malignancies, the cost and complexity of CAR T manufacturing present significant barriers to broader patient access. Beyond manufacturing challenges, ex vivo expansion of T cells may be detrimental to their function and persistence. Thus, delivery of CARs to reprogram host cells in vivo would represent a significant advance towards a readily available therapy, but has been limited by low efficiency, low specificity, and immunogenicity of viral vectors. Here, we describe the design of pseudotyped lentiviral vectors (LV) with superior functionality and high target specificity. We show that LV pseudotyped with chimeric envelope glycoproteins from dolphin morbillivirus (DMV) can be engineered to selectively infect human T cells and evade neutralizing antibody responses in measles-vaccinated human serum. We further demonstrate that camelid-derived nanobodies are a superior retargeting domain, overcoming limitations inherent to the use of single-chain variable fragment antibodies. Using a chimeric DMV-pseudotyped virus targeting the CD7 receptor, we demonstrate efficient and highly specific infection of T cells both in vitro and in vivo, generating functional CAR T cells and inducing therapeutic efficacy in a preclinical B cell lymphoma model.
Author Info: (1) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts Gen
Author Info: (1) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (2) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (3) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (4) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. Dana-Farber Cancer Institute, Gastrointestinal Cancer Center, Boston, MA, USA. (5) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (6) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (7) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (8) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (9) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (10) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. (11) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. yates@broadinstitute.org. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. yates@broadinstitute.org. (12) Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA, USA. rmanguso@broadinstitute.org. Krantz Family Center for Cancer Research and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. rmanguso@broadinstitute.org.
